In a recent assembly line of vehicles or the like, an elongated rectangular-shaped plastic footrest plate is attached to a workpiece such as a vehicle body as often as required. Generally, in order to facilitate the attaching operation of the footrest plate, a pair of mounting holes are formed in the workpiece, and a pair of anchor clips are provides on the rear side (opposite to the footrest side) of the footrest plate in alignment with the pair of mounting holes. Then, the pair of clips are inserted into the corresponding mounting holes to fix the footrest plate to the workpiece. The pair of mounting holes are formed at predetermined positions of the workpiece with leaving a predetermined distance therebetween. Correspondingly, the pair of clips are provided at predetermined positions of the rear side of the footrest plate with leaving a predetermined distance therebetween.
The respective positions and the distance for the pair of mounting holes should match with those for the pair of clips to allow the clips to be inserted into the corresponding mounting holes. However, complicated processes are required to form the mounting holes and the clips with a high degree of positioning accuracy, which leads to undesirably increased cost. From this point of view, each of the mounting holes is formed with a predetermined positional tolerance, and one of the clips is formed with a predetermined clearance for compensating a misalignment caused by the tolerance. In this case, if the attached footrest plate is applied with a certain load from a driver's foot rested thereon, the region of the footrest plate around the reference clip having no clearances can be secured, whereas the remaining region around the other clip is displaced by the clearance. This allows the footrest plate to be rotated several or more degrees around the reference clip, and such a rotational movement is repeatedly caused as a consequence of changes of the direction of the load, resulting in undesirable wobbling movement of the footrest.
Japanese Utility Model Laid-Open No: 62-39007 discloses an assembly for attaching a molding such as a side guard molding to a vehicle body. In this assembly, a plurality of clips are fixed to the molding, and a corresponding number of grommets are fixed to a vehicle body. Then, the clips are inserted into the corresponding grommets to attach the molding to the vehicle body. For allowing the clips to be received into the corresponding grommets even if the distance between the adjacent clips or grommets is varied by dimensional tolerances or thermal expansions, one of the adjacent grommets is arranged to have a longitudinal length greater than that of the other grommet. The assembly described in this publication does not include any suggestion on attachment of a footrest plate. Further, a misalignment caused by tolerances or thermal expansions is compensated by only one grommet. Thus, even if this assembly can be applied to a footrest, the aforementioned rotational or wobbling movement would be caused. Japanese Utility Model Laid-Open No. 01-162847 discloses an assembly for attaching a garnish to a vehicle body. In this assembly, a plurality of clips are fixed to the rear side of the garnish by means of retainers with leaving a predetermined distance therebetween. A plurality of mounting holes are formed in the vehicle body at corresponding positions apart from a predetermined distance therebetween. The retainers are formed with elongated grooves, respectively, extending in one direction to removably hold the clips in the grooves. One of the retainers is formed with an L-shaped groove so that the clip is held immovably in the retainer in the longitudinal direction. As with the aforementioned assembly, the assembly described in this publication does not include any suggestion on attachment of a footrest plate. In particular, this assembly is intended to detachably hold the garnish, and is unsuited for a measure for reducing the rotational or wobbling movement of a footrest plate.
It is therefore an object of the present invention to provide a footrest plate capable of reducing rotational or wobbling movement of the footrest plate attached to a vehicle body or the like.